你的题目是否有错:1/2+1/6+1/12+1/20+1/30+1/42=1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7=1-1/7=6/7若按你的:1/2+1/6+1/12+1/20+1/30*1/42=1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/30*1/42=1-1/5+1/30*1/42=4/5+1/1260=1009/1260